There have been proposed various methods for preparing nanoparticles. Among these methods, flame pyrolysis, spray pyrolysis, a sol-gel process, a solvothermal method and the like, as well as transitional physical pulverizing methods, have been used. In the process of forming nanoparticles, nanoparticles are formed and simultaneously agglomerated because the surface of a nanoparticle is unstable. Therefore, methods for overcoming the agglomeration of nanoparticles have been developed.
Korean Unexamined Patent Application Publication No. 2008-0004831 (applicant: Samsung Electro-Mechanics Co., Ltd.)
discloses a method of preparing metal oxide nanoparticles stabilized by covering the surface of a copper precursor with capping molecules, and metal oxide nanoparticles prepared by this method. Korean Patent No. 820231 (patentee: Samsung Electro-Mechanics Co., Ltd.) discloses a method of preparing metal nanoparticles by spray-injecting a metal precursor solution. Korean Patent No. 790948 (patentee: Samsung Electro-Mechanics Co., Ltd.) discloses a method of preparing metal nanoparticles using a metal precursor solution and a dispersion stabilizer.
Korean Patent No. 790948 (patentee: Sungkyunkwan University Academy-industry Foundation) discloses a method of preparing nanoparticles using an electroless plating solution. Korean Unexamined Patent Application Publication No. 2008-81630 (applicant: Korean Institute of Industrial Technology (KITECH)) discloses a method of preparing nanoparticles by spraying an electroless plating solution on a substrate.
Korean Patent No. 555584 (inventor: Choi Yong-ho) discloses a method of preparing metal nanoparticles using electrolysis. Korean Patent No. 724807 (patentee: Korea University Academy-industry Foundation) discloses a method of preparing tin oxide nanoparticles using oleic acid and tin oxide nanoparticles prepared by this method.
Further, there have also been proposed methods of stabilizing nanoparticles by introducing a ligand such as amine or sodium ascorbate into the nanoparticles to fix the nanoparticles on active carbon, an inorganic oxide, a polymer, zeolite or the like. Korean Unexamined Patent Application Publication No. 10-2008-0021535 (applicant: Yonsei University) discloses a method of modifying the surface of nanoparticles using a multifunctional ligand and a method of preparing water-soluble nanoparticles.
Since nanoparticles stably dispersed in an aqueous solution receive a great deal of attention in the field of biological engineering and medical engineering, the demand thereof is very high internally and externally. Therefore, various technologies for stably dispersing nanoparticles in an aqueous solution have been continuously researched in various manners, and it has been continuously required to develop novel, uniform and stable nanoparticles, and preparation methods thereof.